MXene/zinc ion embedded agar/sodium alginate hydrogel for rapid and efficient sterilization with photothermal and...

Bacterial infections can significantly impair wound healing. Therefore, it is essential to develop wound dressings with high antimicrobial activity. Hydrogels are often used as wound dressings due to their excellent physicochemical properties. Herein, by cross linking sodium alginate (SA), agar (AG) with Ti₃C₂T_x MXene and Zinc ions (Zn²⁺), a biosafe composite hydrogel (MSG-Zn²⁺) was developed for fast and efficient sterilization treatment. The excellent photothermal properties of Ti₃C₂T_x MXene and the chemical antimicrobial activity of Zn²⁺ enable synergistic photothermal therapy (PTT)/chemical therapy in NIR biowindow with reduced power density and improved antimicrobial efficiency. More importantly, the incorporation of Zn²⁺ can enhance the effective contact between the hydrogel and bacteria, benefiting both photothermal and chemical antibacteria. In vitro antibacterial experiments showed that MSG-Zn²⁺ has a broad-spectrum antibacterial effect against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). Cellular experiments showed that the hydrogel had excellent biocompatibility and the released Zn²⁺ stimulated cell migration. In addition, the prepared MSG-Zn²⁺ hydrogel has other advantages such as hydrophilic, high swelling, simple and low cost preparation, which meets the requirements of an economical wound dressing. This proposed work shows that this composite hydrogel MSG-Zn²⁺ has great potential for practical antimicrobial wound dressing applications.